Check that list_samplers returns a list

sherpa/sim/tests/test_sim_unit.py

@@ -0,0 +1,37 @@
+#
+#  Copyright (C) 2017  Smithsonian Astrophysical Observatory
+#
+#
+#  This program is free software; you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation; either version 3 of the License, or
+#  (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License along
+#  with this program; if not, write to the Free Software Foundation, Inc.,
+#  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+#
+
+from sherpa import sim
+
+# This is part of #397
+#
+def test_list_samplers():
+    """Ensure list_samplers returns a list."""
+
+    mcmc = sim.MCMC()
+    samplers = mcmc.list_samplers()
+
+    assert isinstance(samplers, list)
+    assert len(samplers) > 0
+
+    # Test that the expected values exist in this list,
+    # but do not enforce these are the only values.
+    #
+    for expected in ['mh', 'metropolismh']:
+        assert expected in samplers